"Is the boom starting to fade? There are concerns that it may be," said Uwe Parpart, chief strategist and head of research at Reorient Group.

Parpart highlighted a number of headwinds including the impacts of China's ongoing anti-corruption drive and the consequential crackdown on junkets - also known as VIP room promoters - who provide high-rolling players with credit at the casinos.

A total of 63,000 officials have been disciplined this year along, a 34 percent increase on 2013, according to Chinese media reports, and it's believed this had a direct impact on gambling appetite.

"There is also a feeling that saturation may have been reached, combined with the growing attraction of other Asian casinos. Macau's glitzy charms are being duplicated in casinos in Malaysia, the Philippines and Singapore in particular," added Parpart.

A croupier deals a card on a blackjack table inside the Venetian Macao resort and casino, operated by Sands China, in Macau, China.

Also adding to the pain are visa restrictions implemented at the start of July restricting the length of tourists' stay and a slow recovery after the World Cup, which took some gambling business away from casinos.

Grant Govertsen, partner and global analyst at Union Gaming Research Macau, also sounded a bearish note on the region.

"We think the headwinds are going to be there for a long time, likely to the end of the year, potentially through to early next year, primarily driven by a weaker than normal VIP segment," he said. "We're recommending investors stay on the sidelines. There could be more downside."

"Let's be clear the Macau business and gambling sector is not going away, the Chinese have been gambling for thousands of years," John Oh, research analyst for gaming and lodging sectors at CLSA told CNBC Asia's "Rundown" on Friday.

"We've seen a slowdown in VIP and we know what's causing that. We think it's the anti-corruption measures in China," he added.

Oh told CNBC casino operators need to shift their resources away from VIP to the mass market, which is where future profits lie.

"If you look at mass market year to date, we're talking about a sector that's growing north of 32 percent. That's a healthy number. Casino operators are going to have to think about how to shift resources from VIP into mass market because mass market is simply four times as profitable as VIP," he said, adding that Las Vegas casinos' profitability is by contrast nowhere near that of Macau's.